The third fatal shooting of a teenager in south London in less than two weeks has been revealed as the worker of an angry bearded environmentalist.

The Commissioner of the Metropolitan Police, Sir Ian Blair, had called an emergency meeting with senior staff on Thursday to discuss the recent shootings in south London, he suggested there was compelling evidence that it was the work of a vigilante environmentalist offsetting his carbon emissions.

Michael Dosunmu, 15, was shot dead in the bedroom of his Peckham home on 6 February.

Police initially believed he was a victim of mistaken identity, however further inspection of the corpse revealed a carbon footprint, the mark of the killer, on the back of his neck.

Three days earlier, 16-year-old James Andre Smartt-Ford died after he was shot at Streatham Ice Arena. Ice rinks are notorious for the amount of energy they waste and it was a known hunting ground of the green killer.

Neighbours of the boy shot in Clapham North said they were shocked.

Christina Piludu said: "I know he was a good boy. He always respected all of us, but if it means stopping global warming perhaps it was worth it."

In a statement Scotland Yard said: "As is routine, links with recent murders in south London have been investigated, and the motive is clear."

"We would like to reassure the communities in south London that we are taking the current situation very seriously and are doing everything in our power to find the carbon offsetter."

On Thursday, Sir Ian is scheduled to meet officers from the Met's Specialist Crime Directorate, which includes Operation Sandals, a unit tasked with investigating gun crime in the green community.